Portable cutting device



Sept. 22, 1953 H. A. CUMFER PORTABLE CUTTING DEVICE 3 Sheets-Sheet 1 Filed Aug. 6, 1949 Q w n. QN m 1-! l QN I N ITM. -Il \N wm Nm h. Il I Q .I N Q` wmf mK. nm N NN .Q f .T a@ QM. hm mvv my .wmv m.. NN QM.: u wm l l Wm. /NQM I ,1! I uw. w .mi U f( MNM. y Nv`|`ml`mlml| s l\l mK NN NM@ Sept 22, 1953 H. A. CUMFER 2,652,892

PORTABLE CUTTING DEVICE Filed Aug. 6, 1949 5 Sheets-Sheet 2 Sept. 22, 1953 H. A. CUMFER 2,652,892

PORTABLE CUTTING DEVICE Filed Aug. 6, 1949 3 Sheets-Sheet 3 2 E: 7j 26' 42 354] 66 --.l 5;* 70 f 'As 4,( n

17 f4 Jzqmfw: affy film/cef ha@ 7% Patented Sept. 22, 1953 u stasi PORTABLE CUTTING DEVICE Harry A. Cumfer, South Bend, Ind. Garnetta Domke, executrix of sai ceased, assignor of one- Hayes, Chicago, Ill., one-third to Edith Cumfer Thompson,

Donald A. Cumfer, Jr. twelfth to Margaret Ind., one-twelfth to d Harry A. Cumfer, dethird to Lucille Cumfer Whittier, Calif., one-twelfth t Nashville, Tenn., one- L. Dionne Cumfer, and one- Cumfer, South Bend,

twelfth to Harry Cumfer, both of Houston, Tex. Application August 6, 1949, Serial No. 109,030

Claims. l

This invention relates to improvements in cutting devices for sheet or board material such as asphalt saturated siding, roofing material and the like, and refers particularly to a portable cutting device which may be conveniently transported to the situs of the job and may be employed to out material to various dimensions and cut the material in various configurations as required to permit the application of the material for its intended purpose.

One of the important objects of the present invention resides in the provision of a device of the character described which is of relatively light weight and of compact construction and yet is rugged and performs its task as a cutting device most conveniently and eiliciently.

Another important object of the invention resides in the provision of means for cutting sheet or board material wherein relatively large sized sheets or boards may be cut and wherein, normally diiicult interior cuts may be simply and conveniently made. n

Other objects and advantages of the present invention willbe apparent from the accompanying drawings and following detailed description.

In the drawings,

Fig. 1 is a side elevational view, parts being broken away, and parts being shown in section of my improved portable cutter.

Fig. 2 is a top plan view of the device illustrated in Fig. 1.

Fig. 3 is a transverse sectional view taken on line 3-3 of Fig. 1.

Fig. 4 is a horizontal sectional View taken through the stub shaft housing and through one of the cutter heads.

Fig. 5 is a sectional view taken on the line 5--5 of Fig. 2.

Fig. 6 is a detailed sectional view takenon line S-B of Fig. 1.

Referring in detail to the drawing, l indicates the main portion of the frame of the portable cutter, the frame comprising essentially lower shaft housing 2 and upper shaft housing 3 joined together at one end by sprocket housingY t. The lower shaft housing 2 carries a supporting boss 5 and also carries a clampmember t in which a screw l is threadedly positioned, said screw carrying atits upper end an abutment plate and at its opposite end a handle 9 whereby the cutter may be secured to any desired supporting surface l0, the-supporting member l0 being confined between the abutment plate 8 and the boss 5. The sprocket housing 4 extends downwardly beneath the lower shaft housing 2 to form a rear support as shown at I I in Fig. 1 for the device. The shaft housings 2 and 3 adjacent their juncture with the sprocket housing t carry webs l2 which function to reinforce and rigidify the structure.

The extending end of the shaft housing 3 is enlarged as shown best at i3 in Fig. 6, the enlarged portion I3 being bifurcated to provide two spaced bearing arms lll. A stub shaft housing l5 having an enlarged end i6 is adapted to be received between the bearing arms lf3 of the enlarged portion t3 of shaft housing 3. A pair of bolts H extend through-the bearing arms lli and are threadedly engaged with the enlarged portion it of the stub shaft housing l5.

The arrangement is such that the stub shaft housing I5 may be swung through a predetermined angle with respect to the shaft housing 3. As will be hereinafter more fully described this expedient permits the convenient separation of the two cutting knives which constitute the cutting elements of the present device.

A shaft l 8 extends through the entire length of the lower shaft housing 2, said shaft being journalled adjacent both of its ends. Only one of the bearing supports for the shaft i8 is illustrated and constitutes ball bearing assembly I9 which is carried within a boss 20 formed upon the inner face of the sprocket housing It. A similar ball bearing assembly may be employed to support the shaft i8 at its opposite end.

A shaft 2l is positioned in the upper shaft housing 3, said shaft being journalled in ball bearing assembly 22 which is carried by boss 23 formed on the inner face of the sprocket housing il. The opposite end of shaft 2l is keyed to a universal joint 24 (Fig. 6) and a spacer member 25 functions to prevent excess axial movement of the shaft 2| within the upper shaft housing 3. A stub shaft 25 is positioned within the stub shaft housing l5 and is keyed at one end to the universal joint 24 which is carried within a housing provided by the enlarged member I8. In normal operation shafts 2| and 26 are in axial alignment with each other and shaft housings 3 and l5 are also in axial alignment with each other. However, when stub shaft housing l5 is swung about the pivot bolts Il with respect to shaft housing 3 the shafts 2l and 26 will be disposed angularly with respect to each other. As will be hereinafter more fully described the shaft 2i comprises a driving shaft and the stub shaft 26 comprises a driven shaft. To permit the stub shaft housing It-to be swung with respect to the shaft housing 3 the juncture between the two shafts 2| and 25 comprising the universal joint 24 will permit such swinging motion to occur. It will be noted that the axis of articulation of the universal joint 24 occurs along the axis of the pivot bolts I1.

A sprocket wheel 21 is mounted upon the end of shaft E8 which projects into the sprocket housing 4. An identical sprocket wheel 2S is similarly mounted upon that end of shaft 2I which projects into the sprocket housing. A sprocket chain 23 is trained around both sprocket wheels 21 and 28, said chain being driven by sprocket wheel 33. A closure 3I is removably mounted upon sprocket housing 4 and is secured thereto by means of screws 32. An electric motor 33 is mounted upon the closure 3I and is secured thereto by means of bolts 34. Dis posed in operative relationship to the electric motor 33 a gear reducing mechanism of conventional construction 35 is carried ladjacent the motor 33. A shaft 36 projects from the gear reducing mechanism 35 into the sprocket housing 4 through opening 31 in closure 3l, said shaft carrying and actuating the sprocket wheel 30. In this manner both shafts I8 and 2l are rotated.

Referring particularly to Figs. 4 and 5, the shaft housing?. is enlarged at its end and is provided with a relatively enlarged bore 33. Similarly the stub shaft housing I is enlarged at its end and is provided with a relatively enlarged bore 39. In the enlarged bore 38 a worm 45 is carried upon the end of shaft I8 and in the enlarged bore 33 a worm 4I is carried upon the end of stub shaft 23. The Worms 45 and 4I are respectively secured to the shafts I8 and 2E by means of keys 42. At the end of each of the enlarged portions of the shaft housings 2 and I5, a plug 43 is positioned, one plug being threadedly engaged in each of the bores 38 and 39. By the provision of the plugs 43, worms 45 and 4I may be mounted or removed from the respective shafts upon which they are mounted and lubricant may be introduced into the enlarged bore.

A housing 44 comprises an integral portion of the end of the shaft housing 2 adjacent the bore 33. In said housing a shaft 45 is journaled in bearings 4S. A worm wheel 41 is carried upon an end of shaft 45 and is adapted to mesh with the worm 43. rlhe worm Wheel 41 is non-rotatably secured to shaft 45 by means of key 48 and longitudinal movement of the Worm Wheel 41 is prevented by means of bolt 49 which engages the end of shaft 45.

Similarly a housing 5l] comprises an integral portion of the end of stub shaft housing I5 and a shaft 5I is journaled in a bearing 52 in said housing. A Worm wheel 53 is non-rotatably secured to shaft 5I by means of key 54 and a bolt 55 functions to prevent axial movement of the Worm wheel.

Closure plates 56 and 51 58 respectively to the housings 44 and 55.

It will be noted by reference particularly to Figs. 2 and 4 that the shafts 45 and 5I are disposed at an obtuse angle to the shafts I8 and 25, respectively. The purpose of this arrangement will be hereinafter more fully described.

Companion collars 53 and 59 are mounted upon an end of shaft 45 which projects from housing 44. The companion collar 59 is provided with an annular slot 63 in which a circular cutting knife 5| is positioned. The arrangement is such that when the companion collars are mounted upon shaft l45 they form a roll which confines the knife 5I between them rendering said knife relatively immovable with respect to said QQllXS-- A are secured by screws nut 62 threadedly engages the end of shaft 45 and functions to confine the knife 5I under pressure between the companion collars 53 and `59. A semi-circular housing 63 is mounted upon the housing 44 and provides a semi-annular trough 64 through which the lowerehalf portion of the knife 6I travels. An absorbent material or wicking 65 is positioned in the semi-annular trough 64, said absorbent material, during operation of the device being saturated with water, oil or the like. The knife 5i in passing through the semi-annular housing B4 cuts through the absorbent material B5 and in this manner the surface of the knife 6I is continuously wetted.

Companion collars 63 and S1 are mounted upon an end of shaft 6I which protrudes from hous ing 5D. The collar 51 is provided with an ann nular slot 63 which is adapted to receive a circular cutting knife 59. A nut "Ill is threadedly engaged upon the end of shaft 5I and functions to confine the knife 39 between the companion collars 55 and 51.

A semi-circular member 13 is mounted upon the upper portion of housing 50, said member being provided with a semi-annular trough 1I which is adapted to carry a quantity of absorbent material 12. The upper portion of the semicircular member 10 is provided with an opening 13 (Fig. 2) which connects with the semi-annular trough 1I. The absorbent material 12 is adapted to be saturated with water, oil or the like which may be introduced into the semi-annular trough through the opening 13. The knife 59 at the upper half of its travel cuts through the absorbent material 12 carried in the trough H and in this manner the cutting surface of said knife is continuously wetted.

When the device Iis in operative position the cutting heads comprising the housings 44 and 55 and the knives 5I and 33 together with their respective retaining members, are disposed adjacent each other in such fashion that the straight or unbevelled portions of the knives are disposed adjacent each other as shown best in Fig. 5. It will be noted that the surfaces of companion collar 58 and companion collar 61 are provided with annular grooves 14 and 15, respectively. The length of the cutting portion of each of the knives is such that when the knives are disposed in cutting position the cutting edges of the knives 6I and 59, respectively, enter the grooves 15 and 14. During the cutting operation the surfaces of the collars 58, 59, 53 and 51 bear with pressure upon the surface of the material being cut which tends to densify the material being out along the lines of incision. In this manner a neat, clean cut is effected and the material adjacent the cut edges being densified, tends to prevent the entrance of water or moisture during use. When cutting asphalt saturated board, for example, the edged portions are not only densified but portions of the asphalt are smeared by the bevelled portions of the knives over the cut edges, tending to form an edge seal.

A pair of spaced lugs 16 is mounted upon the the upper portion of the stub shaft housing I5. A lug 11 is mounted upon the enlarged end of shaft housing 3. A bifurcated bell crank lever 18 is pivotally secured by means of pivot pin 19 to lug 11. One arm of the bell crank lever 18 carries a handle and the opposite arm thereof is pivotally connected to a link 8| by means of pivot pin 82. The opposite end of link BI is pivotally connected to the spaced lugs 16 by means of pivot pin 83.

A lug 84 is carried upon the bottom portion attacca of the-stub shaft rhousing i5, :said :.lugbeing aper- 'tured to :receive vthe :end `of bolt lie, :said :bolt .be-

The arrangement is such that under normal g circumstances spring B8 tends to rock the stub shaft `housing f5 `and the cutting head vcarried thereon about .the pivot bolts il, `the motion being counterclockwise as viewed in Fig. l.. To lower the `cutting head tooperative cutting ,position, handle 80 is moved in aclockwise VAdirection as viewed in Fig. l about the pivotl. In isoswinging the handle V8l) the bell crank lever 7:8 :moves the stub shaft housing downwardly :through the agency of link 8l against the compressive vtorce of spring .88. This movement .continues until the cutting heads are in Loperative cutting position as shown in Fig. 5 at which time one arm of the bell crank lever 'lll and the linksil-'are disposed substantially in dead .center fpositionqor slightly below dead center position.

A stop 89 is formed upon stub shaft housing l5 and functions to limit the clockwise movement of the bell crank lever 18.

In utilizing my invention, the device may be mounted as hereinbefore described upon any suitable support by means of the clamping arrangement comprising the screw l and lug 5. With the absorbent wickings 65 and l2 thoroughly saturated with water, oil or the like, the mac terial to be cut, that is the asphalt saturated siding, roofing or the like, is positioned above the lowermost knife 6| with the upper cutting head in upraised position. The line of cut may previously have been inscribed upon the material to be cut and with said line disposed in proper relationship to the lowermost knife, motor 33 may be set into operation and by the manipulation of handle 30, that is the movement thereof in a clockwise direction as viewed in Fig. l, the upper cutting head may be lowered to operative cutting position, the toggle mechanism associated with the handle d@ functioning to lock the upper cutting head in its cutting position. The cut may then conveniently C be made, a portion of the cut material straddling the spaces between the opposed cutting heads and the sprocket housing 4. It will be noted that by disposing the cutting heads at an obtuse angle to their respective drive shafts IB and E5,

a portion of the material to be cut will pass between the cutting heads and the sprocket housing d at an angle and consequently I have found this to be the most convenient disposition of the cutting heads.

Of course, it is to be understood that the cutting heads may be disposed at substantially any angle with respect to the shafts I8 and 26, respectively. However, in general, it is believed that the angular disposition of the cutting heads provides the greatest flexibility of use.

It is desirable before lowering the upper cutting head to cutting position that the motor be set into operation so that the load may be placed on the motor more or less gradually. In addition, by the provision of the swingable upper cutting head, interior cuts may be most conveniently made, the handle 8l) being manipulated to start and stop the cutting operation. In this fashion, square or triangular or rectangu- '6 Ilarvopenin'gs :may be cutiin" theinterior `ofpzthe area of the `board and by 'the .properzmanipuiation `fof 'the .board during the cutting operation, `arcuate `lines tof cut `may falso be tmade' within the :area fof 'the board.

In view fof the fact .that this 'device :is particularly `'applicable to :the cutting vof materials which: are 'saturated with asphalt, .the 'provision vfor-wetting* the knives proves most convenient Land makes -the cutting `operation easier to per- "form. However, it is'to beunderstood 'that'my device,- although particularly adaptable for cutting saturated board or roofing can be employed 'to cut any 'type' of 'fibrous material, plastic material-or even thin gauge metals.

In order to conveniently move and carry :my portable cutter,-1a handle |21 may be carried upon the Vuppers'haft housing `3 of the Vform of my vv'invention `illustrated `in `Figs. 1 to 6, inclusive.

Itwill 'be understood by those yskilled in the art `that many modifications of kmy 'invention may be made without departing from the spirit thereof, and'consequently I do not wish to vlbe limited except as `necessitated by the 'priorart I claim 'as my invention:

A 1. A portable cutting device comprisingin combirra-tion, Ya frame co pri'sing Vtwo spaced arms, a cutting head carried by each arm, one of said arms being pivoted intermediate its length to move said cutting heads toward and away from each other, means for rotating said cutting heads, each cutting head comprising a circular cutting knife, means for locking said pivoted arm with the knives of said cutting head in shearing relation to each other, and means intermediate of and on one of said arms for moving that part of said pivoted ar-m which carries the cutting head away from the other arm to permit disposition of material to be cut between said cutting heads.

2. A portable cutting device comprising in combination, a frame comprising two spaced arms, a cutting head carried by each arm, one of said arms being pivoted intermediate its length to move said cutting heads toward and away from each other, means for rotating said cutting heads, each cutting head comprising a circular cutting knife, toggle means for locking said pivoted arm with the knives of said cutting head in shearing relation to each other, and means intermediate of and on one of said arms for moving that part of said pivoted arm which carries the cutting head away from the other arm to permit disposition of material to be cut between said cutting heads.

3. A portable cutting device comprising in combination, a frame comprising two spaced arms, a cutting head carried by each arm, one of said arms being pivoted intermediate its length to move said cutting heads toward and away from each other, means for rotating said cutting heads, each cutting head comprising a circular cutting knife, toggle means for locking said pivoted arm with the knives of said cutting head in shearing relation to each other, means intermediate of and on one of said arms for moving that part of said pivoted arm which carries the cutting head away from the other arm to permit disposition of material to be cut between said cutting heads, and resilient means for holding said arms in separated relationship with respect to each other.

4. A cutting device comprising in combination, a frame comprising two spaced arms, a cutting head carried by each arm, means for rotating said cutting heads one of said arms being pivoted intermediate its length to move said cutting heads toward and away from each other, said means comprising a shaft carried by each arm and operatively connected to each cutting head a universal joint carried intermediate the length of the shaft carried by the pivoted arm to permit swingable movement of the shaft with the arm, and means carried by said frame for driving said shafts to rotate said cutting heads, each cutting head comp-rising a circular cutting knife, means for positioning those portions of said arms which carry said cutting heads relative to each other to dispose the cutting knives in shearing relation to each other, and means intermediate of and on one of said arms for separating said cutting heads with respect to each other to dispose therebetween rnaterial to be cut.

5. A cutting device comprising in combination, a frame comprising two spaced arms, a cutting head carried by each arm, means for rotating said cutting heads, said means comprising a shaft carried by each arm and operatively connected to each cutting head a universal joint disposed intermediate the length of one shaft, the arm carrying said last mentioned shaft being pivoted to permit simultaneous swingable movement of said arm and shaft, and means carried by said frame for driving said shafts to rotate said cutting heads,` said means comprising an electric motor and sprocket means connecting said motor and shafts in driving relation, each cutting head comprising a circular cutting knife, means for positioning said arms relative to each other to dispose the cutting knives in shearing relation to each other, and means for separating said cutting heads with respect to each other to dispose therebetween material to be cut.

HARRY A. CUMFER.

References Cited in the le of this patent UNITED STATES PATENTS Number Name Date 453,380 Tincher June 2, 1891 740,730 Zeh Oct. 6, 1903 898,259 Preston Sept. 8, 1908 963,610 Matheus July 5, 1910 1,143,594 Fuhry June 15, 1915 1,150,928 Cesar Aug. 24, 1915 1,235,192 Dougall July 31, 1917 1,722,549 Wills July 30, 1929 FOREIGN PATENTS Number Country Date 761,677 France Mar. 24, 1934 

